Positive PD-L1 Expression Predicts Worse Outcome in Cutaneous Angiosarcoma

Advancing Cancer Research: Current Knowledge on Cutaneous Neoplasia

Skin cancers require a multidisciplinary approach. The updated guidelines introduce new insights into the management of these diseases. Melanoma (MM), the third most common skin cancer, a malignant melanocytic tumor, which is classified into four major histological subtypes, continues to have the potential to be a lethal disease. The mortality-incidence ratio is higher in Eastern European countries compared to Western European countries, which shows the need for better prevention and early detection in Eastern European countries. Basal cell carcinoma (BCC) and squamous cell carcinoma (cSCC) remain the top two skin cancers, and their incidence continues to grow. The gold standard in establishing the diagnosis and establishing the histopathological subtype in BCC and SCC is a skin biopsy. Sebaceous carcinoma (SeC) is an uncommon and potentially aggressive cutaneous malignancy showing sebaceous differentiation. It accounts for 0.7% of skin cancers and 3-6.7% of cancer-related deaths. Due to the rapid extension to the regional lymph nodes, SeC requires early treatment. The main treatment for sebaceous carcinoma is surgical treatment, including Mohs micrographic surgery, which has the advantage of complete margin evaluation and low recurrence rates. Primary cutaneous lymphomas (PCLs) are a heterogeneous group of lymphoproliferative diseases, with no evidence of extracutaneous determination at the moment of the diagnosis. PCLs have usually a very different evolution, prognosis, and treatment compared to the lymphomas that may secondarily involve the skin. The aim of our review is to summarize the important changes in the approach to treating melanoma, non-melanoma skin, cutaneous T and B cell lymphomas, and other types of skin cancers. For all skin cancers, optimal patient management requires a multidisciplinary approach including dermatology, medical oncology, and radiation oncology.

Tumor Microenvironment and Its Clinicopathologic and Prognostic Association in Cutaneous and Noncutaneous Angiosarcomas

OBJECTIVES

We explored features of the angiosarcoma (AS) tumor microenvironment to discover subtypes that may respond to immunotherapy.

METHODS

Thirty-two ASs were included. Tumors were studied by histology, immunohistochemistry (IHC), and gene expression profile using the HTG EdgeSeq Precision Immuno-Oncology Assay.

RESULTS

Comparing cutaneous and noncutaneous ASs, the second group showed 155 deregulated genes, and unsupervised hierarchical clustering (UHC) delineated two groups: the first mostly cutaneous AS and the second mainly noncutaneous AS. Cutaneous ASs showed a significantly higher proportion of T cells, natural killer cells, and naive B cells. ASs without MYC amplification revealed a higher immunoscore in comparison with ASs with MYC amplification. PD-L1 was significantly overexpressed in ASs without MYC amplification. UHC showed 135 deregulated genes differentially expressed when comparing ASs from the non-head and neck area with patients who had AS in the head and neck area. ASs from the head and neck area showed high immunoscore. PD1/PD-L1 content was significantly more highly expressed in ASs from the head and neck area. IHC and HTG gene expression profiling revealed a significant correlation between PD1, CD8, and CD20 protein expression but not PD-L1.

CONCLUSIONS

Our HTG analyses confirmed a high degree of tumor and microenvironment heterogeneity. Cutaneous ASs, ASs without MYC amplification, and ASs located in the head and neck area seem to be the most immunogenic subtypes in our series.

PD-L1 Expression in Cutaneous Angiosarcomas: A Systematic Review with Meta-Analysis

Cutaneous angiosarcoma (CAS) is the most common type of angiosarcoma that predominantly affects older Caucasians. The outcomes of immunotherapy in CAS are currently under investigation in relation to the expression of programmed death ligand 1 (PD-L1) and other biomarkers. We performed a systematic review and metanalysis of data from the current literature reporting on PD-L1 immunohistochemistry expression. A systematic search of publications in the electronic databases PubMed, Web of Science, and Scopus was conducted using the following terms: "PD-L1" and "angiosarcomas". A total of ten studies reporting on 279 cases were identified and included in the meta-analysis. The pooled prevalence of PD-L1 expression in CAS was 54% (95% CI 36-71%), with high heterogeneity (I² = 84.81%, p < 0.001). In sub-group analysis, the proportion of PD-L1 expression in CAS was significantly (p = 0.049) lower in Asian studies (ES = 35%, 95% CI 28-42%, I² = 0.0%, p = 0.46) than in European studies (ES = 71%, 95% CI 51-89%, I² = 48.91%, p = 0.12).

The role of PD-1/PD-L1 and application of immune-checkpoint inhibitors in human cancers

Programmed cell death protein-1 (PD-1) is a checkpoint receptor expressed on the surface of various immune cells. PD-L1, the natural receptor for PD-1, is mainly expressed in tumor cells. Studies have indicated that PD-1 and PD-L1 are closely associated with the progression of human cancers and are promising biomarkers for cancer therapy. Moreover, the interaction of PD-1 and PD-L1 is one of the important mechanism by which human tumors generate immune escape. This article provides a review on the role of PD-L1/PD-1, mechanisms of immune response and resistance, as well as immune-related adverse events in the treatment of anti-PD-1/PD-L1 immunotherapy in human cancers. Moreover, we summarized a large number of clinical trials to successfully reveal that PD-1/PD-L1 Immune-checkpoint inhibitors have manifested promising therapeutic effects, which have been evaluated from different perspectives, including overall survival, objective effective rate and medium progression-free survival. Finally, we pointed out the current problems faced by PD-1/PD-L1 Immune-checkpoint inhibitors and its future prospects. Although PD-1/PD-L1 immune checkpoint inhibitors have been widely used in the treatment of human cancers, tough challenges still remain. Combination therapy and predictive models based on integrated biomarker determination theory may be the future directions for the application of PD-1/PD-L1 Immune-checkpoint inhibitors in treating human cancers.

Tumor microenvironment and its clinicopathological and prognostic associations in surgically resected cutaneous angiosarcoma

PURPOSE

Cutaneous angiosarcoma (CAS) is a rare but typically aggressive malignant vascular neoplasm of the skin. Tumor microenvironment (TME) of CAS and its associations with baseline clinicopathological features and patient outcomes are very important, especially when considering the recent advances in understanding of the tumor biology.

METHODS/PATIENTS

We retrospectively reviewed medical records of patients who underwent surgical resection for CAS at a tertiary Hospital. The pretreated specimens were evaluated by immunohistochemistry for programmed cell death protein 1 (PD-1) and its ligand (PD-L1), densities of tumor infiltrative lymphocytes (TILs) (CD3+, CD4+, CD8+, CD45RO+, FoxP3+), as well as c-MYC and Ki-67 expressions. Overall survival (OS) was estimated by Kaplan-Meier method and compared with Log-rank test.

RESULTS

A total of 21 CAS patients were identified. Median age was 67 (ranges: 20-81) years, 14 (66.7%) were male, and over 50% had lesions of scalp. Histopathological examination showed a predominantly spindle cell type (57.1%). All patients underwent surgery, 16 (76.2%) were treated further. PD-L1 was positively stained (> 1%) in tumor cells (42.9%) and TILs (23.8%). PD-1 expression (> 1%) was identified in TILs of 11 (52.4%) cases. PD-1/PD-L1 expressions were significantly associated with the higher densities of CD3+, CD4+, CD8+, CD45RO+, and Foxp3+ TILs, but not with patient characteristics or c-MYC or Ki-67 expression. Median OS was 18.5 months (95% CI 6.0-35.9), although no prognostic significance was observed with respect to any clinicopathological features.

CONCLUSION

We characterized TME and its clinical and prognostic association in CAS. PD-1/PD-L1 expressions were significantly associated with TILs subtypes but not with OS.

Kutane Angiosarkome: molekulare Pathogenese und neue therapeutische Ansätze

Das kutane Angiosarkom (CAS) ist ein hochaggressiver maligner Tumor mit schlechter Prognose. Das primäre, spontane CAS (pCAS) und das sekundäre, mit einer Bestrahlung oder einem Lymphödem assoziierte CAS (sCAS) unterscheiden sich klinisch sowie molekular. Die Amplifikation/Überexpression von Myc ist ein charakteristisches, wenn auch nicht ausschließliches Merkmal von sCAS, während der Verlust von TP53 selektiv bei pCAS vorkommt. Detaillierte molekulare Analysen mit modernen Multi-Omics-Ansätzen haben gezeigt, dass sowohl pCAS als auch sCAS eine erhebliche molekulare Heterogenität aufweisen. Die betroffenen Gene und ihre molekularen Regulatoren sind mögliche therapeutische Zielstrukturen. Darüber hinaus kann das pCAS in Cluster mit hoher Mutationsrate und/oder ausgeprägten Entzündungssignaturen eingeteilt werden, die als Grundlage für die künftige Stratifizierung von pCAS-Patienten in immuntherapeutischen klinischen Studien dienen können. Während die Aufklärung der der Erkrankung zugrunde liegenden molekularen Veränderungen zügig voranschreitet, verläuft die Entwicklung daraus abgeleiteter neuer Therapien für das CAS jedoch bisher eher langsam. Dennoch wurden einige über die Standardtherapien wie Operation und Radiochemotherapie hinausgehende klinische Studien zu neuen Behandlungsmöglichkeiten initiiert. Dazu gehören zielgerichtete Therapien gegen VEGF und VEGFR1-3 wie Bevacizumab und Pazopanib, sowie β-Adrenozeptorenblocker wie Propranolol. Derzeit werden auch Immuntherapien entwickelt, unter anderem unter Verwendung der Immuncheckpoint-Inhibitoren Pembrolizumab und Nivolumab sowie des Anti-RANKL-Antikörper Denosumab.

Clinical, genomic, and transcriptomic correlates of response to immune checkpoint blockade-based therapy in a cohort of patients with angiosarcoma treated at a single center

Background

Angiosarcoma is a histologically and molecularly heterogeneous vascular neoplasm with aggressive clinical behavior. Emerging data suggests that immune checkpoint blockade (ICB) is efficacious against some angiosarcomas, particularly cutaneous angiosarcoma of the head and neck (CHN).

Methods

Patients with histologically confirmed angiosarcoma treated with ICB-based therapy at a comprehensive cancer center were retrospectively identified. Clinical characteristics and the results of targeted exome sequencing, transcriptome sequencing, and immunohistochemistry analyses were examined for correlation with clinical benefit. Durable clinical benefit was defined as a progression-free survival (PFS) of ≥16 weeks.

Results

For the 35 patients included in the analyses, median PFS and median overall survival (OS) from the time of first ICB-based treatment were 11.9 (95% CI 7.4 to 31.9) and 42.5 (95% CI 19.6 to 114.2) weeks, respectively. Thirteen patients (37%) had PFS ≥16 weeks. Clinical factors associated with longer PFS and longer OS in multivariate analyses were ICB plus other therapy regimens, CHN disease, and white race. Three of 10 patients with CHN angiosarcoma evaluable for tumor mutational burden (TMB) had a TMB ≥10. Five of six patients with CHN angiosarcoma evaluable for mutational signature analysis had a dominant mutational signature associated with ultraviolet (UV) light. No individual gene or genomic pathway was significantly associated with PFS or OS; neither were TMB or UV signature status. Analyses of whole transcriptomes from nine patient tumor samples found upregulation of angiogenesis, inflammatory response, and KRAS signaling pathways, among others, in patients with PFS ≥16 weeks, as well as higher levels of cytotoxic T cells, dendritic cells, and natural killer cells. Patients with PFS <16 weeks had higher numbers of cancer-associated fibroblasts. Immunohistochemistry findings for 12 patients with baseline samples available suggest that neither PD-L1 expression nor presence of tumor-infiltrating lymphocytes at baseline appears necessary for a response to ICB-based therapy.

Conclusions

ICB-based therapy benefits only a subset of angiosarcoma patients. Patients with CHN angiosarcoma are more likely to have PFS ≥16 weeks, a dominant UV mutational signature, and higher TMB than angiosarcomas arising from other primary sites. However, clinical benefit was seen in other angiosarcomas also and was not restricted to tumors with a high TMB, a dominant UV signature, PD-L1 expression, or presence of tumor infiltrating lymphocytes at baseline.

Cutaneous Angiosarcomas: Molecular Pathogenesis Guides Novel Therapeutic Approaches

Cutaneous angiosarcoma (CAS) is a highly aggressive cancer with a poor prognosis. Primary, spontaneous CAS (pCAS) and secondary, post-irradiation- or lymphedema-associated CAS (sCAS) are clinically, but also molecularly distinct. Myc amplification/overexpression is a characteristic, although not exclusive feature of sCAS, while loss of TP53 selectively occurs in pCAS. Detailed molecular analyses with modern multi-omics approaches have revealed that both pCAS and sCAS exhibit considerable molecular heterogeneity. Affected genes and their molecular regulators including a plethora of microRNAs may serve as future drug targets. Furthermore, pCAS could be subdivided into clusters with high tumor mutational burden and/or high tumor inflammation signatures providing a rationale for the stratification of pCAS patients in future immunotherapeutic clinical studies. Development of novel treatment regimens guided by these molecular alterations, however, cannot fully keep up with the pace of their discovery due to the low incidence of the disease. Nevertheless, beyond conventional surgery and chemoradiotherapy, clinical trials investigating novel treatment options have been initiated including targeted therapies against VEGF and VEGFR1-3 such as bevacizumab and pazopanib, and β-adrenoreceptor blockers such as propranolol. Finally, immunotherapies are being developed including immune checkpoint inhibitors pembrolizumab and nivolumab as well as anti-RANKL antibody denosumab.

Analysis of PD-1, PD-L1, and T-cell infiltration in angiosarcoma pathogenetic subgroups

Angiosarcoma (AS) is a rare malignancy with a poor prognosis. It can develop spontaneously or due to previous radiotherapy (RT), ultraviolet (UV) radiation, or lymphoedema (Stewart Treves AS). Novel therapeutic approaches are needed, but progress is hindered because of the heterogeneity and rarity of AS. In order to explore the potential of immune checkpoint inhibition (ICI), we investigated the protein expression of programmed cell death 1 (PD-1), programmed death-ligand 1 (PD-L1), and CD8 + T cells in 165 AS cases in relation to AS subgroups based on clinical classification and in relation to whole-genome methylation profiling based clusters (A1, A2, B1, B2). High PD-L1 and PD-1 expression were predominantly shown in UV-associated, visceral, and soft tissue AS. RT-associated AS showed predominantly high PD-1 expression. CD8 + T cell infiltration was present in the majority of AS samples. Within the UV-associated AS, two different clusters can be distinguished by DNA methylation profiling. Cases in cluster A1 showed higher PD-1 (p = 0.015), PD-L1 (p = 0.015), and CD8 + T cells (p = 0.008) compared to those in cluster B2, suggesting that these UV-AS tumors are more immunogenic than B2 tumors showing a difference even within one subgroup. In soft tissue AS, combined PD-1 and PD-L1 expression showed a trend toward poor survival (p = 0.051), whereas in UV-associated AS, PD-1 expression correlated with better survival (p = 0.035). In conclusion, we show the presence of PD-1, PD-L1, and CD8 + T cells in the majority of AS but reveal differences between and within AS subgroups, providing prognostic information and indicating to be predictive for ICI.

Malignant Vascular Tumors of the Head and Neck-Which Type of Therapy Works Best?

Simple Summary

Malignant vascular tumors are extremely rare tumors with variable clinical courses, and few data on their clinical management are available. Diagnosis is difficult due to their wide morphologic appearance. The intent of the present review is to demonstrate the current knowledge and management on malignant vascular tumors of the head and neck area. The mainstay of treatment for malignant vascular tumors is surgery, but radiotherapy and chemotherapy are also parts of the treatment concept especially in angiosarcomas. Targeted therapy, antiangiogenetic drugs and immunotherapy have been studied as new treatment options.

Abstract

Malignant vascular tumors of the head and neck are rare neoplasms with variable clinical presentation, wide age distribution, and variable clinical courses. The heterogeneous presentation of angiosarcomas and epithelioid hemangioendothelioma often leads to misdiagnosis and unsuitable treatment. While risk factors for angiosarcomas are previous radiation, chronic lymphedema, and exposure to arsenic, thorium oxide, or vinyl chloride, there are only limited and retrospective data available on prognostic factors in EHE. In both angiosarcomas and EHE, surgery is the mainstay of treatment. There is limited evidence regarding the role of radiotherapy in EHE, although EHE is considered relatively radiosensitive. In angiosarcomas, adjuvant radiotherapy is recommended according to retrospective case series. A standard medical therapy for metastasized malignant vascular tumors is lacking. Chemotherapy, which is effective in angiosarcoma, is mostly ineffective in EHE. Targeted therapy, antiangiogenetic drugs and immunotherapy have been studied as new treatment options. The goal of this review is to summarize the current data regarding malignant vascular tumors along with their diagnosis and management.

Abscopal Effects in Metastatic Cancer: Is a Predictive Approach Possible to Improve Individual Outcomes?

Patients with metastatic cancers often require radiotherapy (RT) as a palliative therapy for cancer pain. RT can, however, also induce systemic antitumor effects outside of the irradiated field (abscopal effects) in various cancer entities. The occurrence of the abscopal effect is associated with a specific immunological activation in response to RT-induced cell death, which is mainly seen under concomitant immune checkpoint blockade. Even if the number of reported apscopal effects has increased since the introduction of immune checkpoint inhibition, its occurrence is still considered rare and unpredictable. The cases reported so far may nevertheless allow for identifying first biomarkers and clinical patterns. We here review biomarkers that may be helpful to predict the occurrence of abscopal effects and hence to optimize therapy for patients with metastatic cancers.

Immune Checkpoint Markers in Superficial Angiosarcomas: PD-L1, PD-1, CD8, LAG-3, and Tumor-Infiltrating Lymphocytes

ABSTRACT

Cutaneous angiosarcomas may express programmed death ligand-1 (PD-L1) and PD-L1 expression, and the presence of tumor-infiltrating lymphocytes (TILs) correlates with outcome. These observations provide a basis for PD-1/PD-L1 inhibitor therapy. Lymphocyte activation gene 3 (LAG-3) is an inhibitory receptor that interacts with the PD-L1 axis and is considered to be a marker of immune exhaustion. The presence of LAG-3-positive lymphocytes in cutaneous angiosarcoma has not been established. We reviewed 10 cases of treatment naive angiosarcoma of skin and superficial soft tissue and assessed for PD-L1 (ZR3) expression, presence of TILs, and expression of CD8, PD1, and LAG-3 by tumor-associated inflammatory cells by immunohistochemistry. All 10 angiosarcomas were positive for PD-L1: 7 with high expression and 3 with low expression. TILs were present in all tumors: brisk in 7 and nonbrisk in 3. CD8 lymphocytes were present in all tumors with a range of 212-1274 cells per square millimeter (mean 557 CD8 cells/mm2). LAG-3-positive lymphocytes were present in 9 of 10 angiosarcomas with a range of 0-728 cells/mm2 (mean 146 LAG-3 cells cells/mm2). The ratio of LAG-3 lymphocytes to CD8 lymphocytes was 0%-59% (mean 27%). The PD1 cell counts were intermediate between CD8 and LAG3 counts. Cutaneous angiosarcomas frequently express PD-L1, have prominent numbers of CD8 positive, and have smaller numbers of LAG-3-positive and PD-1-positive TILs. Our findings provide further evidence of PD-L1 expression in cutaneous angiosarcoma and the promise for immune checkpoint inhibitor therapy.

Expression of Programmed Cell Death Proteins in Kaposi Sarcoma and Cutaneous Angiosarcoma

Not only for cutaneous angiosarcoma (CAS) patients but also for advanced and therapy-refractory patients with classic Kaposi sarcoma (CKS) and human immunodeficiency virus (HIV)-associated Kaposi sarcoma (HIV-KS) there is a high need for more effective treatment modalities. The aim of this work was to study programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) protein expression and related immune parameters in CKS, HIV-KS, and CAS and correlate it with other immunologic parameters and clinical data. Immunohistochemistry was performed on formalin-fixed paraffin-embedded tumor tissue of 19 CKS, 7 HIV-KS, and 12 CAS patients using antibodies against the following (and they are): PD-1, PD-L1, CD4, CD8, CD56, and FOXP3. PD-1 expression significantly correlated with PD-L1 expression Moreover, PD-1 and PD-L1 expression significantly correlated with CD56 and FOXP3 expression. High intratumoral FOXP3 expression was significantly associated with disease relapse (P=0.029). CD4 and FOXP3 expression was significantly higher in CKS and CAS, as compared with HIV-KS. All in all, PD-1 and PD-L1 expression was relatively weak and did not significantly differ between CKS, HIV-KS, and CAS patients. Nevertheless, PD-1 was positive in 31.6% of CKS, 28.6% of HIV-KS, and 33.3% of CAS patients. PD-L1 was expressed in 36.6% of CKS, 28.6% of HIV-KS, and 41.7% of CAS patients. We have provided evidence that PD-1/PD-L1 signalling is of importance in angiosarcomas such as CKS, HIV-KS, and CAS. Our results support the notion that the use of PD-1/PD-L1 inhibitors may represent an effective strategy against these tumors.

Histopathologic PD-L1 Tumor Expression and Prognostic Significance in Nonmelanoma Skin Cancers: A Systematic Review

ABSTRACT

PD-L1 and PD-1 inhibitors are being increasingly used to treat a variety of nonmelanoma skin cancers (NMSCs). This systematic review summarizes PD-L1 expression in NMSCs and determines its use for prognosis using targeted immunotherapy. A primary search of peer-reviewed English-language medical literature was conducted for studies on PD-L1 tumor expression in biopsied or excised NMSCs. Fifty-nine articles met criteria for inclusion. PD-L1 expression in advanced NMSCs ranged from 22%-89% for basal cell carcinomas, 42%-50% for Merkel cell carcinomas, and 26%-100% for squamous cell carcinomas. Study limitations included clone heterogeneity across studies, complicating comparison of PD-L1 expression. Differences were also noted in the selection of tumor reactivity threshold. We conclude that there is insufficient evidence to determine the prognostic significance of PD-L1 expression in NMSCs as a whole, but this remains a promising area. More investigation into the role of tumor PD-L1 as a biomarker for predicting clinical response to PD-L1 and PD-1 inhibitors in NMSCs is needed.

Prognostic implications of PD-L1 expression in patients with angiosarcoma

Aim:

There are limited data on the feasibility of programmed death ligand-1 (PD-L1) expression as a prognostic biomarker in metastatic angiosarcoma.

Patients & methods:

We retrospectively collected and analyzed the data on PD-L1 expression in 70 angiosarcoma patients who were diagnosed at our center between 2005 and 2019.

Results:

Thirteen (19%) patients had PD-L1 expression. Metastatic angiosarcoma patients who were PD-L1-negative (n = 24) showed longer median progression-free survival (4.9 vs 1.6 months; p = 0.04) and median overall survival (OS; 10.9 vs 5.4 months; p = 0.01) than those who were PD-L1-positive (n = 4). PD-L1 status proved to be a significant factor for OS.

Conclusion:

Metastatic angiosarcoma patients with PD-L1 expression showed shorter survival. PD-L1 status is an independent prognostic factor for OS in metastatic angiosarcoma patients.

Angiosarcoma, a rare subtype of sarcoma, is highly aggressive and has poor prognosis. The majority of patients are diagnosed at advanced and metastatic stages, and treatment options for these subsets of patients are limited to cytotoxic chemotherapy. Validation of prognostic markers including PD-L1 expression remain to be fully carried out in metastatic angiosarcoma. In our study, we assessed the PD-L1 expression in metastatic angiosarcoma and its role as a prognostic biomarker.

Optimal Clinical Management and the Molecular Biology of Angiosarcomas

Angiosarcomas comprise less than 3% of all soft tissue sarcomas but have a poor prognosis. Most angiosarcomas occur without obvious risk factors but secondary angiosarcoma could arise after radiotherapy or chronic lymphedema. Surgery remains the standard treatment for localized angiosarcoma but neoadjuvant systemic treatment may improve the curability. For advanced angiosarcoma, anthracyclines and taxanes are the main chemotherapy options. Anti-angiogenic agents have a substantial role but the failure of a randomized phase 3 trial of pazopanib with or without an anti-endoglin antibody brings a challenge to future trials in angiosarcomas. Immune checkpoint inhibitors as single agents or in combination with oncolytic virus may play an important role but the optimal duration remains to be investigated. We also report the current understanding of the molecular pathways involved in angiosarcoma pathogenesis including MYC amplification, activation of angiogenic pathways and different molecular alterations that are associated with angiosarcomas of different aetiology. The success of the patient-partnered Angiosarcoma Project (ASCProject) has provided not only detailed insights into the molecular features of angiosarcomas of different origins but also offers a template for future fruitful collaborations between patients, physicians, and researchers. Lastly, we provide our perspective of future developments in optimizing the clinical management of angiosarcomas.

Stewart-Treves syndrome: Case report and literature review

Lymphangiosarcoma, or Stewart-Treves Syndrome (STS), is a very rare skin angiosarcoma with poor prognosis, which usually affects the upper limbs of patients who underwent breast cancer surgery, including axillary dissection followed by radiotherapy (RT). Cutaneous lymphangiosarcomas, which account for approximately 5% of all angiosarcomas, usually originate in the limb with chronic lymphedema. Lymphatic blockade is involved in the onset of STS. RT contributes indirectly to an increased risk of developing STS by causing axillary-node sclerosis and resulting in a lymphatic blockade and lymphedema. Chronic lymphedema causes local immunodeficiency, which indirectly leads to oncogenesis. Currently, axillary nodes are no longer routinely irradiated after axillary dissection, which is associated with a reduction in the incidence of chronic lymphedema from 40% to 4%. The use of sentinel lymph node biopsy technique is also widespread and the associated risk of lymphedema is further reduced. Thus, the incidence of STS decreased significantly with improved surgical and radiation techniques. The overall prognosis of STS patients is very poor. Only early radical surgical removal, including amputation or disarticulation of the affected limb, or wide excision at an early stage offers the greatest chance of long-term survival. Only a few case reports and series with a small number of patients with lymphangiosarcoma can be found in the literature. We present a case report of the first diagnosed STS at our department in an effort to highlight the need of the consideration of developing lymphangiosarcoma in patients with chronic lymphedema.

Angiosarcomas: histology, immunohistochemistry and molecular insights with implications for differential diagnosis

Angiosarcomas (AS) represent a heterogenous group of tumors with variable clinical presentation. AS share an important morphologic and immunohistochemical overlap with other sarcomas, hence the differential diagnosis is challenging, especially in poorly-differentiated tumors. Although molecular studies provide significant clues, especially in the differential diagnosis with other vascular neoplasms, a thorough hematoxylin and eosin analysis remains an essential tool in AS diagnosis. In this review, we discuss pathological and molecular insights with emphasis on implications for differential diagnosis in cutaneous, breast, soft tissue and visceral AS.

Primary and secondary cutaneous angiosarcoma: Distinctive clinical, pathological and molecular features

Angiosarcomas are ubiquitous neoplasms involving both cutaneous and soft tissue and visceral locations. Accumulating biomolecular evidences suggest that cutaneous angiosarcomas are distinctive entities with molecular, clinical and pathological peculiarities. Despite several ongoing clinical trials with promising therapeutic agents, the prognosis of cutaneous angiosarcomas is dismal and survival still rely on early diagnosis and surgery. An accurate diagnosis and the knowledge of the underlying molecular landscape are therefore essential to improve the prognosis. We detail the molecular, clinical, dermoscopic, morphological and prognostic features of cutaneous angiosarcoma. Although the molecular landscape of cutaneous angiosarcoma is not completely understood, accumulating evidences suggest that there are characteristic molecular alterations including dysregulation of angiogenesis and several complex molecular pathways. Secondary cutaneous angiosarcomas, arising in correlation with chronic lymphedema and ionizing radiation, have different molecular hallmarks, which are also leading to the first diagnostic applications. The diagnosis of cutaneous angiosarcoma may be challenging, as well-differentiated forms can be hard to distinguish from benign and low-grade vascular neoplasms, while poorly differentiated forms can be easily confounded with other non-vascular high-grade neoplasms. An accurate and early diagnosis, which is mandatory to ensure the best survival for the patients, is mainly based on morphological hallmarks.

Retrospective analysis of the prognostic value of PD-L1 expression and 18F-FDG PET/CT metabolic parameters in colorectal cancer

Background: It has been rarely reported whether ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) uptake in colorectal cancer cells is associated with the expression of PD-L1. We performed a clinical pathology study to evaluate PD-L1 expression in patients undergoing surgical resection of colorectal cancer with preoperative ¹⁸F-FDG PET/CT imaging, with the aim of predicting the response of CRC patients to immune checkpoint inhibitors.

Material and Methods: A retrospective analysis of patients with CRC who underwent FDG-PET imaging before surgery was performed to measure the parameters of FDG-PET imaging: the maximum standardized uptake value (SUVmax), the metabolic tumor volume (MTV), and the total lesion glycolysis (TLG) were evaluated to determine whether each parameter was associated with clinical pathology. Tumor specimens were subjected to PD-L1 staining by immunohistochemistry. Analysis of whether there is a correlation between PD-L1 expression and ¹⁸F-FDG uptake parameters in CRC.

Results: PD-L1 expression level was significantly correlated with SUVmax, MTV3.0 and TLG3.0. Multivariate analysis showed that PD-L1 and TLG3.0 were independent predictors of poor DFS in patients with CRC (P=0.009; P=0.016), PD-L1 expression is closely related to the patient's lesion (TLG3.0) (P<0.01).

Conclusion: The results of this study indicate that there was a significant correlation between PD-L1 expression and TLG3.0 which suggested that FDG-PET could serve as a noninvasive tool to assess the tumor microenvironment and as a predictor of PD-L1 inhibitor activity to determine the optimal therapeutic strategy for CRC. High PD-L1 expression levels and high TLG3.0 are independent risk factors for DFS differences in CRC patients.

Predictive biomarkers and mechanisms underlying resistance to PD1/PD-L1 blockade cancer immunotherapy

Immune checkpoint blockade targeting PD-1/PD-L1 has promising therapeutic efficacy in a variety of tumors, but resistance during treatment is a major issue. In this review, we describe the utility of PD-L1 expression levels, mutation burden, immune cell infiltration, and immune cell function for predicting the efficacy of PD-1/PD-L1 blockade therapy. Furthermore, we explore the mechanisms underlying immunotherapy resistance caused by PD-L1 expression on tumor cells, T cell dysfunction, and T cell exhaustion. Based on these mechanisms, we propose combination therapeutic strategies. We emphasize the importance of patient-specific treatment plans to reduce the economic burden and prolong the life of patients. The predictive indicators, resistance mechanisms, and combination therapies described in this review provide a basis for improved precision medicine.

[Cutaneous angiosarcoma : Radiochemotherapy with liposomal pegylated doxorubicin]

BACKGROUND

Whilst cutaneous angiosarcoma is rare tumour which primarily affects elderly patients, its management presents a significant therapeutic challenge. Indeed, complete surgical excision is often not possible due to the location and the diffuse and extensive nature of the tumour. Therefore, current treatment strategies often include chemo- and/or radiotherapy.

METHODS

We report our experience of combined chemo- and radiotherapy in the clinical course of 6 patients with cutaneous angiosarcoma who were treated between 2007 and 2018.

RESULTS

All patients presented non-resectable tumours and were treated with radiotherapy in combination with the administration of liposomal, pegylated doxrubicin (25 mg/m² every 2 weeks). The mean duration of progression-free survival was 8 months (5-14 months), corresponding to an overall survival of 13 months (13-34 months). A partial response was seen in 4 patients and 1 patient developed progressive disease. One patient abandoned therapy after one administration. Two patients developed severe adverse events which led to termination of therapy after 1.5 months and 7 months, i.e. after 4 and 15 cycles respectively.

DISCUSSION

Combined radio- and chemotherapy with liposomal, pegylated doxorubicin is a useful therapeutic option in the management of cutaneous angiosarcoma. Given the short-lived response rate, new treatment options are urgently required.

Regulation of programmed cell death ligand 1 expression by atypical protein kinase C lambda/iota in cutaneous angiosarcoma

The expression of immune checkpoint proteins such as programmed cell death protein 1 (PD‐1) and its ligand (PD‐L1) has been shown to correlate with patient prognosis in many malignant cancers. The expression of PD‐L1 is controlled by c‐Myc; however, further upstream regulation of PD‐L1 expression is largely unknown. We have previously shown that atypical protein kinase C lambda/iota (aPKCλ) phosphorylates the Forkhead box protein O1 (FoxO1) transcription factor at Ser218 to suppress its DNA‐binding ability, thereby regulating c‐Myc expression and controlling physiologic and pathologic endothelial proliferation. The presence of phosphorylation of FoxO1 at Ser218 (pSer218 FoxO1) in cutaneous angiosarcoma (CAS) strongly correlates with poor patient prognosis. Here, we reported that patients with PD‐L1⁺ cells in CAS lesions showed significantly worse prognosis compared to those that were PD‐L1⁻. Expression of PD‐L1 correlated with that of aPKCλ or the presence of pSer218FoxO1. Moreover, suppression of aPKCλ expression or inhibition of its activity in HUVECs or AS‐M, an established human angiosarcoma cell line, resulted in decreased PD‐L1 expression. Our results suggest that combined treatment with immune checkpoint inhibitors and aPKCλ inhibitors could be a novel treatment strategy for CAS patients.

Angiosarcoma with Synchronous Cutaneous and Small Bowel Involvement: A Report of a Rare Presentation

Angiosarcomas are mesenchymal neoplasms of vascular origin that represent approximately 2% of soft tissue sarcomas. We discuss the case of a 75-year-old female who had presented with a purple nodular rash along the bilateral nasolabial folds. Upon further work-up, she was diagnosed with angiosarcoma, with the confirmed involvement of multi-focal sites. These included biopsy proven sites of the face and duodenum along with the radiographic involvement of the lungs, liver, and osseous tissue. We report this unique presentation of a rare malignancy and the treatment course with radiation, paclitaxel, and bevacizumab. We also discuss the implications of her co-morbid liver cirrhosis and gastric antral vascular ectasia (GAVE) in terms of its influence on the development of the angiosarcoma and treatment response.

Association Between Programmed Death-Ligand 1 Expression and the Vascular Endothelial Growth Factor Pathway in Angiosarcoma

Angiosarcoma is a vascular malignancy associated with a poor prognosis and chemotherapy resistance. The tumor immune microenvironment of angiosarcoma has not been characterized. We investigated the expression of programmed death-ligand 1 (PD-L1) and programmed death 1 (PD-1) in angiosarcoma and correlated these findings with vascular endothelial growth factor (VEGF)-related gene expression and survival. Using archived formalin-fixed paraffin-embedded tissues of primary and metastatic angiosarcoma specimens, we characterized the immunohistochemical (IHC) expression of PD-L1 and PD-1. In addition, we extracted RNA from each tumor and quantified the expression of VEGF-related genes, and then tested if these genes were associated with PD-L1 and PD-1 expression and clinical outcomes. Retrospective review identified 27 angiosarcoma specimens collected between 1994 and 2012. IHC expression of tumor PD-L1, tumor-infiltrating immune cell PD-L1, and tumor-infiltrating immune cell PD-1 expression was identified in 5 (19%), 9 (33%), and 1 (4%) specimens, respectively. Expression of PD-L1 and PD-1 was not associated with VEGF-related gene expression or survival. PD-L1 tumor and tumor-infiltrating immune cells expression was identified in a large proportion of patients. Though neither was associated with VEGF-related gene expression or prognosis, targeting PD-1/PD-L1 may be of benefit for a significant proportion of angiosarcomas that do not respond to surgery, chemotherapy, or radiation.

Cutaneous angiosarcoma: update on biology and latest treatment

PURPOSE OF REVIEW

The present review aims to provide readers with the latest updates on the biology and clinical management of cutaneous angiosarcoma (cAS).

RECENT FINDINGS

The genomic alteration of cAS is heterogeneous. Mutations are enriched in the mitosis-activated kinase (MAPK) pathway. Functional analysis has identified molecules that may serve as potential markers and therapeutic targets of angiosarcoma. These molecules include survivin, HSP90, FOXM1, miR-497-5p, KCa3.1, and miR210.This body of knowledge has not yet transferred to clinical practice. The mainstay of treatment for cAS remains surgery followed by postoperative radiotherapy. The efficacy of paclitaxel as an adjuvant chemotherapy is suggested.For patients with advanced cAS, paclitaxel is the treatment of choice. There are also second-line treatment options that are supported by evidence of varying strength. A multikinase inhibitor, pazopanib, has been assessed in several studies, most of which support its efficacy for angiosarcoma. Bevacizumab monotherapy may be effective for angiosarcoma. The efficacy of eribulin mesylate and trabectedin for angiosarcoma is currently being assessed. Recent publications highlighted the role of the immune system in the biology of cAS.

SUMMARY

Future research efforts should focus on the following aspects of cAS: drug development directed at recent molecular targets, clinical trials designed specifically for patients with cAS, and the role of immunotherapy for cAS.